Head cracked
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From: Yuba city Kalifornia
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From: Isanti, MN
The higher the cylinder pressure, the more the engine is trying to blow the head off the engine. Since there can't be a head bolt every inch, this causes stress between the bolts (made worse because only one cylinder at a time is firing). The injector holes are a big weakness in the structural rigidity of the head.
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From: Tijeras, New Mexico, 7,000ft up
I disagree. If the head bolts flex around each cylinder as it hits, the head will bend and eventually crack. My head bolts were getting quite spongy and wouldn't torque anymore. My head was lifting and dumping antifreeze every time I got on it. The side of the block looks like a cave wall because so much coolant has run down it. It's completely my fault. I feel stupid, but live and learn.
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From: Thunder Bay
I disagree. If the head bolts flex around each cylinder as it hits, the head will bend and eventually crack. My head bolts were getting quite spongy and wouldn't torque anymore. My head was lifting and dumping antifreeze every time I got on it. The side of the block looks like a cave wall because so much coolant has run down it. It's completely my fault. I feel stupid, but live and learn.
Look on PayBay, er, you know where I am talking about.
Fully loaded heads are listed for $465, I offered $430 and they took it right away. Should have started at $400!
On the cracks, if I had studded it before I put all my power adders on it might not have cracked. After at least 200K with 40psi was too much for the head bolts, and lifting the head probably flexed it enough to crack the heck out of it. I don't see how the 24 valve guys keep their heads together at all without studs.
Fully loaded heads are listed for $465, I offered $430 and they took it right away. Should have started at $400!
On the cracks, if I had studded it before I put all my power adders on it might not have cracked. After at least 200K with 40psi was too much for the head bolts, and lifting the head probably flexed it enough to crack the heck out of it. I don't see how the 24 valve guys keep their heads together at all without studs.
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From: Tijeras, New Mexico, 7,000ft up
No, not genuine Cummins, but probably practically the same. For me it was $430 (which I can barely afford) or $1,400 for Cummins, which I could not afford.
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From: Thunder Bay
wow seriously? that's pretty bad. that the old head? please tell me thats not the head you bought...
the cracks between the valves that i had were worse, but i didn't have nearly as many as that.
the cracks between the valves that i had were worse, but i didn't have nearly as many as that.
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From: Maryland
While the topic is being discussed, please allow Me to ask a question.
I have a 89 non IC head, on mine and I don't ever run as high boost #'s as many of You since mine is only mildly tunned up and I try to keep it bellow 30psi. One day when the time comes to do a HG job on it and I where to find stress crack such as the ones You pictured, should I have them repair the head? The machine shop guy said they can weld the cracks on some heads hot tank them or something and re-use them I consider this as an option since the other option would be a IC head and smaller injectors I just want to keep the same one I have. Could You give Me some advise, thanks.
I have a 89 non IC head, on mine and I don't ever run as high boost #'s as many of You since mine is only mildly tunned up and I try to keep it bellow 30psi. One day when the time comes to do a HG job on it and I where to find stress crack such as the ones You pictured, should I have them repair the head? The machine shop guy said they can weld the cracks on some heads hot tank them or something and re-use them I consider this as an option since the other option would be a IC head and smaller injectors I just want to keep the same one I have. Could You give Me some advise, thanks.
